American Water Heater 240HX3 Installation Manual And Owner's Manual page 29

To determine the dimension of a common-venting system
Determine the vent diameter (D) and the total vent length based on the number of water heaters installed. The
total vent length (L) consists of the horizontal width (W) and the vertical height (H). See the table below
•
Total vent length (L)="H"+"W"+
(Number of Elbows X 5)
•
Vent diameter="D"
• Regarding the clearances
NOTICE
between the exhaust
termination and the intake
termination, refer to pages
14 to 16.
• Insert bird screen in elbow
terminations.
X3™ CARTRIDGE NOT SHOWN.
• A Non-Return Valve must be installed for each water heater. This prevents the escape of
combustion gas through non-operating appliances.
• For detailed instructions on the common-venting system, refer to the instructions that are
packaged with the vent parts or web site.
WARNING
Common-venting system
Max.
Vent
No. of
Diameter*
water
(Total) Vent Length** (L)
(D)
heaters
4 in 2
2
5 in
3
2
3
6 in 4
5
6
3
4
5
8 in
6
7
8
5
6
10 in
7
8
*Diameters of pipes are in accordance with Centrotherm's specifications.
**One elbow is equivalent to 5 ft (1.5 m) linear length, and the maximum number of elbows is 5.
Max. Vertical and
Horizontal DIP switch settings
25 ft (7.6 m)
50 ft (15.2 m)
20 ft (6.1 m)
100 ft (30.5 m)
240HX3/340HX3 Indoor
75 ft (22.9 m)
ON 1 2 3 4 5 6 7 8 9 10
50 ft (15.2 m
OFF
25 ft (7.6 m)
No. 6 : ON / No. 7: OFF
20 ft (6.1 m)
100 ft (30.5 m)
100 ft (30.5 m)
85 ft (25.9 m)
65 ft (19.8 m)
50 ft (15.2 m)
41 ft (12.5 m)
No. 3 : ON / No. 4: OFF
100 ft (30.5 m)
100 ft (30.5 m)
100 ft (30.5 m)
100 ft (30.5 m)
29
"H"
Non-Return Valve
540HX3 Indoor
(Upper bank of
DIP switches)
ON 1 2 3 4 5 6 7 8
OFF
Page
Installation Manual
Installation
.
Elbow terminal
Elbow terminal
Exhaust
Intake
"D"
" W "
WARNING
• Adjust the appropriate DIP
switches according to model
as shown in the left table.
DO NOT adjust the other DIP
switches.
(Refer to page 23 for the
location of the DIP switches.)
• Turn off the power supply
to the water heater before
changing the DIP switch set-
tings.
• Failure to observe these
warnings could lead to car-
bon monoxide poisoning or
death.